@
Means ALL
The at sign (@) means “all” in some fashion:
/list @ {all lines in a file}
/help list,@ {all information about List}
/:listf @.source {all files in a group}
/l "Cu@"(pattern) {all strings starting with “Cu”}
The abbreviation for “all lines” is @ by default, but can be changed with the Set Zip command.